US 11,690,285 B2
Electroluminescent devices
Nicholas J. Thompson, New Hope, PA (US); Chun Lin, Yardley, PA (US); and Hsiao-Fan Chen, Lawrence Township, NJ (US)
Assigned to UNIVERSAL DISPLAY CORPORATION, Ewing, NJ (US)
Filed by Universal Display Corporation, Ewing, NJ (US)
Filed on May 24, 2021, as Appl. No. 17/328,403.
Application 17/328,403 is a continuation in part of application No. 17/090,265, filed on Nov. 5, 2020.
Application 17/090,265 is a continuation in part of application No. 16/841,182, filed on Apr. 6, 2020.
Application 16/841,182 is a continuation in part of application No. 16/683,507, filed on Nov. 14, 2019.
Claims priority of provisional application 62/772,403, filed on Nov. 28, 2018.
Prior Publication US 2021/0305520 A1, Sep. 30, 2021
Int. Cl. H01L 51/00 (2006.01); C07F 5/02 (2006.01); C09K 11/06 (2006.01); C07D 403/14 (2006.01); C07F 7/08 (2006.01); C07F 15/00 (2006.01); H01L 51/50 (2006.01)
CPC H01L 51/0087 (2013.01) [C07D 403/14 (2013.01); C07F 5/027 (2013.01); C07F 7/0812 (2013.01); C07F 15/0086 (2013.01); C09K 11/06 (2013.01); H01L 51/008 (2013.01); H01L 51/0067 (2013.01); H01L 51/0071 (2013.01); H01L 51/0072 (2013.01); H01L 51/0094 (2013.01); C07B 2200/05 (2013.01); C09K 2211/1018 (2013.01); C09K 2211/1048 (2013.01); C09K 2211/185 (2013.01); H01L 51/5016 (2013.01); H01L 2251/5384 (2013.01); H01L 2251/552 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An organic light emitting device (OLED) having an emission spectrum, the OLED comprising:
an anode;
a cathode; and
an organic emissive layer, disposed between the anode and the cathode, comprising:
a first host material having a highest occupied molecular orbital (HOMO) energy and a lowest unoccupied molecular orbital (LUMO) energy; and
an emitter material having a HOMO energy and a LUMO energy;
wherein,
all materials in the organic emissive layer are mixed together;
the emitter material is a phosphorescent metal complex;
High HOMO energy is the highest HOMO energy among all materials in the organic emissive layer;
Low LUMO energy is the lowest LUMO energy among all materials in the organic emissive layer;
a≤ET−ΔE≤b, wherein ET is triplet energy T1 of the emitter material, which is the lowest T1 energy among all materials in the organic emissive layer, ΔE is the energy gap between the High HOMO energy and the Low LUMO energy, a is 0.00 up to 0.15 eV, and b is 0.05 up to 0.45 eV; and
wherein root mean squared function (RMSD) value for the emission spectrum of the OLED and an emission spectrum of a reference OLED, whose organic emissive layer consists of the emitter material and an inert host, is not greater than 0.05,
wherein RMSD value is a single value that represents the average difference between the emission spectrum of the OLED and the emission spectrum of the reference OLED at all wavelengths obtained by the following equation:

OG Complex Work Unit Math
wherein n is the number of points on the two emission spectrums being compared, and I1 and I2 are the normalized intensity spectrums as a function of wavelength, λ.